John Siracusa > Rose-Object-0.859 > Rose::Object::MakeMethods::Generic

Download:
Rose-Object-0.859.tar.gz

Dependencies

Annotate this POD

Website

CPAN RT

Open  0
View/Report Bugs
Module Version: 0.859   Source   Latest Release: Rose-Object-0.860

NAME ^

Rose::Object::MakeMethods::Generic - Create simple object methods.

SYNOPSIS ^

  package MyObject;

  use Rose::Object::MakeMethods::Generic
  (
    scalar => 
    [
      'power',
      'error',
    ],

    'scalar --get_set_init' => 'name',

    'boolean --get_set_init' => 'is_tall',

    boolean => 
    [
      'is_red',
      'is_happy' => { default => 1 },
    ],

    array =>
    [
      jobs       => {},
      job        => { interface => 'get_set_item', hash_key => 'jobs' },
      clear_jobs => { interface => 'clear', hash_key => 'jobs' },
      reset_jobs => { interface => 'reset', hash_key => 'jobs' },
    ],

    hash =>
    [
      param        => { hash_key => 'params' },
      params       => { interface => 'get_set_all' },
      param_names  => { interface => 'keys', hash_key => 'params' },
      param_values => { interface => 'values', hash_key => 'params' },
      param_exists => { interface => 'exists', hash_key => 'params' },
      delete_param => { interface => 'delete', hash_key => 'params' },

      clear_params => { interface => 'clear', hash_key => 'params' },
      reset_params => { interface => 'reset', hash_key => 'params' },
    ],
  );

  sub init_name    { 'Fred' }
  sub init_is_tall { 1 }
  ...

  $obj = MyObject->new(power => 5);

  print $obj->name; # Fred

  $obj->do_something or die $obj->error;

  $obj->is_tall;        # true
  $obj->is_tall(undef); # false (but defined)
  $obj->is_tall;        # false (but defined)

  $obj->is_red;         # undef
  $obj->is_red(1234);   # true
  $obj->is_red('');     # false (but defined)
  $obj->is_red;         # false (but defined)

  $obj->is_happy;       # true

  $obj->params(a => 1, b => 2);   # add pairs
  $val = $obj->param('b');        # 2
  $obj->param_exists('x');        # false

  $obj->jobs('butcher', 'baker'); # add values
  $obj->job(0 => 'sailor');       # set value
  $job = $obj->job(0);            # 'sailor'

DESCRIPTION ^

Rose::Object::MakeMethods::Generic is a method maker that inherits from Rose::Object::MakeMethods. See the Rose::Object::MakeMethods documentation to learn about the interface. The method types provided by this module are described below. All methods work only with hash-based objects.

METHODS TYPES ^

scalar

Create get/set methods for scalar attributes.

Options
hash_key

The key inside the hash-based object to use for the storage of this attribute. Defaults to the name of the method.

init_method

The name of the method to call when initializing the value of an undefined attribute. This option is only applicable when using the get_set_init interface. Defaults to the method name with the prefix init_ added.

interface

Choose one of the two possible interfaces. Defaults to get_set.

Interfaces
get_set

Creates a simple get/set accessor method for an object attribute. When called with an argument, the value of the attribute is set. The current value of the attribute is returned.

get_set_init

Behaves like the get_set interface unless the value of the attribute is undefined. In that case, the method specified by the init_method option is called and the attribute is set to the return value of that method.

Example:

    package MyObject;

    use Rose::Object::MakeMethods::Generic
    (
      scalar => 'power',
      'scalar --get_set_init' => 'name',
    );

    sub init_name { 'Fred' }
    ...

    $obj->power(99);    # returns 99
    $obj->name;         # returns "Fred"
    $obj->name('Bill'); # returns "Bill"
boolean

Create get/set methods for boolean attributes. For each argument to these methods, the only thing that matters is whether it evaluates to true or false. The return value is either, true, false (but defined), or undef if the value has never been set.

Options
default

Determines the default value of the attribute. This option is only applicable when using the get_set interface.

hash_key

The key inside the hash-based object to use for the storage of this attribute. Defaults to the name of the method.

init_method

The name of the method to call when initializing the value of an undefined attribute. Again, the only thing that matters about the return value of this method is whether or not is is true or false. This option is only applicable when using the get_set_init interface. Defaults to the method name with the prefix init_ added.

interface

Choose one of the two possible interfaces. Defaults to get_set.

Interfaces
get_set

Creates a simple get/set accessor method for a boolean object attribute. When called with an argument, the value of the attribute is set to true if the argument evaluates to true, false (but defined) otherwise. The current value of the attribute is returned.

If Class::XSAccessor version 0.14 or later is installed and the ROSE_OBJECT_NO_CLASS_XSACCESOR environment variable is not set to a true value, then Class::XSAccessor will be used to generated the method.

get_set_init

Behaves like the get_set interface unless the value of the attribute is undefined. In that case, the method specified by the init_method option is called and the attribute is set based on the boolean value of the return value of that method.

Example:

    package MyObject;

    use Rose::Object::MakeMethods::Generic
    (
      'boolean --get_set_init' => 'is_tall',

      boolean => 
      [
        'is_red',
        'is_happy' => { default => 1 },
      ],
    );

    sub init_is_tall { 'blah' }
    ...

    $obj->is_tall;        # returns true
    $obj->is_tall(undef); # returns false (but defined)
    $obj->is_tall;        # returns false (but defined)

    $obj->is_red;         # returns undef
    $obj->is_red(1234);   # returns true
    $obj->is_red('');     # returns false (but defined)
    $obj->is_red;         # returns false (but defined)

    $obj->is_happy;       # returns true
hash

Create methods to manipulate hash attributes.

Options
hash_key

The key inside the hash-based object to use for the storage of this attribute. Defaults to the name of the method.

init_method

The name of the method to call when initializing the value of an undefined hash attribute. This method should return a reference to a hash, and is only applicable when using the get_set_init interface. Defaults to the method name with the prefix init_ added.

interface

Choose which interface to use. Defaults to get_set.

Interfaces
get_set

If called with no arguments, returns a list of key/value pairs in list context or a reference to the actual hash stored by the object in scalar context.

If called with one argument, and that argument is a reference to a hash, that hash reference is used as the new value for the attribute. Returns a list of key/value pairs in list context or a reference to the actual hash stored by the object in scalar context.

If called with one argument, and that argument is a reference to an array, then a list of the hash values for each key in the array is returned.

If called with one argument, and it is not a reference to a hash or an array, then the hash value for that key is returned.

If called with an even number of arguments, they are taken as name/value pairs and are added to the hash. It then returns a list of key/value pairs in list context or a reference to the actual hash stored by the object in scalar context.

Passing an odd number of arguments greater than 1 causes a fatal error.

get_set_init

Behaves like the get_set interface unless the attribute is undefined. In that case, the method specified by the init_method option is called and the attribute is set to the return value of that method, which should be a reference to a hash.

get_set_inited

Behaves like the get_set interface unless the attribute is undefined. In that case, it is initialized to an empty hash before proceeding as usual.

get_set_all

If called with no arguments, returns a list of key/value pairs in list context or a reference to the actual hash stored by the object in scalar context.

If called with one argument, and that argument is a reference to a hash, that hash reference is used as the new value for the attribute. Returns a list of key/value pairs in list context or a reference to the actual hash stored by the object in scalar context.

Otherwise, the hash is emptied and the arguments are taken as name/value pairs that are then added to the hash. It then returns a list of key/value pairs in list context or a reference to the actual hash stored by the object in scalar context.

get_set_init_all

Behaves like the get_set_all interface unless the attribute is undefined. In that case, the method specified by the init_method option is called and the attribute is set to the return value of that method, which should be a reference to a hash.

clear

Sets the attribute to an empty hash.

reset

Sets the attribute to undef.

delete

Deletes the key(s) passed as arguments. Failure to pass any arguments causes a fatal error.

exists

Returns true of the argument exists in the hash, false otherwise. Failure to pass an argument or passing more than one argument causes a fatal error.

keys

Returns the keys of the hash in list context, or a reference to an array of the keys of the hash in scalar context. The keys are not sorted.

names

An alias for the keys interface.

values

Returns the values of the hash in list context, or a reference to an array of the values of the hash in scalar context. The values are not sorted.

Example:

    package MyObject;

    use Rose::Object::MakeMethods::Generic
    (
      hash =>
      [
        param        => { hash_key =>'params' },
        params       => { interface=>'get_set_all' },
        param_names  => { interface=>'keys',   hash_key=>'params' },
        param_values => { interface=>'values', hash_key=>'params' },
        param_exists => { interface=>'exists', hash_key=>'params' },
        delete_param => { interface=>'delete', hash_key=>'params' },

        clear_params => { interface=>'clear', hash_key=>'params' },
        reset_params => { interface=>'reset', hash_key=>'params' },
      ],
    );
    ...

    $obj = MyObject->new;

    $obj->params; # undef

    $obj->params(a => 1, b => 2); # add pairs
    $val = $obj->param('b'); # 2

    %params = $obj->params; # copy hash keys and values
    $params = $obj->params; # get hash ref

    $obj->params({ c => 3, d => 4 }); # replace contents

    $obj->param_exists('a'); # false

    $keys = join(',', sort $obj->param_names);  # 'c,d'
    $vals = join(',', sort $obj->param_values); # '3,4'

    $obj->delete_param('c');
    $obj->param(f => 7, g => 8);

    $vals = join(',', sort $obj->param_values); # '4,7,8'

    $obj->clear_params;
    $params = $obj->params; # empty hash

    $obj->reset_params;
    $params = $obj->params; # undef
array

Create methods to manipulate array attributes.

Options
hash_key

The key inside the hash-based object to use for the storage of this attribute. Defaults to the name of the method.

init_method

The name of the method to call when initializing the value of an undefined array attribute. This method should return a reference to an array. This option is only applicable when using the get_set_init, push, and add interfaces. When using the get_set_init interface, init_method defaults to the method name with the prefix init_ added.

interface

Choose which interface to use. Defaults to get_set.

Interfaces
get_set

If called with no arguments, returns the array contents in list context or a reference to the actual array stored by the object in scalar context.

If called with one argument, and that argument is a reference to an array, that array reference is used as the new value for the attribute. Returns the array contents in list context or a reference to the actual array stored by the object in scalar context.

If called with one argument, and that argument is not a reference to an array, or if called with more than one argument, then the array contents are replaced by the arguments. Returns the array contents in list context or a reference to the actual array stored by the object in scalar context.

get_set_init

Behaves like the get_set interface unless the attribute is undefined. In that case, the method specified by the init_method option is called and the attribute is set to the return value of that method, which should be a reference to an array.

get_set_inited

Behaves like the get_set interface unless the attribute is undefined. In that case, it is initialized to an empty array before proceeding as usual.

get_set_item

If called with one argument, returns the item at that array index.

If called with two arguments, sets the item at the array index specified by the first argument to the value specified by the second argument.

Failure to pass any arguments causes a fatal error.

exists

Returns true of the argument exists in the hash, false otherwise. Failure to pass an argument or passing more than one argument causes a fatal error.

add

An alias for the push interface.

push

If called with a list or a reference to an array, the contents of the list or referenced array are added to the end of the array. If called with no arguments, a fatal error will occur.

pop

Remove an item from the end of the array and returns it. If an integer argument is passed, then that number of items is removed and returned. Otherwise, just one is removed and returned.

shift

Remove an item from the start of the array and returns it. If an integer argument is passed, then that number of items is removed and returned. Otherwise, just one is removed and returned.

unshift

If called with a list or a reference to an array, the contents of the list or referenced array are added to the start of the array. If called with no arguments, a fatal error will occur.

clear

Sets the attribute to an empty array.

reset

Sets the attribute to undef.

Example:

    package MyObject;

    use Rose::Object::MakeMethods::Generic
    (
      array =>
      [
        jobs       => {},
        job        => { interface => 'get_set_item', 
                        hash_key  => 'jobs' },
        clear_jobs => { interface => 'clear', hash_key => 'jobs' },
        reset_jobs => { interface => 'reset', hash_key => 'jobs' },
      ],
    );
    ...

    $obj = MyObject->new;

    $jobs = $obj->jobs; # undef

    $obj->clear_jobs();
    $jobs = $obj->jobs; # ref to empty array

    $obj->jobs('butcher', 'baker'); # add values
    $vals = join(',', $obj->jobs);  # 'butcher,baker'

    $obj->jobs([ 'candlestick', 'maker' ]); # replace values

    $vals = join(',', $obj->jobs); # 'candlestick,maker'

    $job = $obj->job(0);      # 'candlestick'
    $obj->job(0 => 'sailor'); # set value
    $job = $obj->job(0);      # 'sailor'

    $obj->reset_jobs;
    $jobs = $obj->jobs; # undef

AUTHOR ^

John C. Siracusa (siracusa@gmail.com)

LICENSE ^

Copyright (c) 2010 by John C. Siracusa. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

syntax highlighting: